The new OutputInitResult is a struct return type that allows
logger init functions to return a NULL context without
raising error.
Instead of returning NULL to signal error, the "ok" field will
be set to false. If ok, but the ctx is NULL, then silently
move on to the next logger.
Use case: multiple versions of a specific logger, and one
implementation decides the configuration is not for that
implemenation. It can return NULL, ok.
For loggers that register once per direction, use unique id's per
direction.
Reshuffle id's to keep tx log id's low so we can use u32 for tracking
logged loggers.
Many were using AlertJsonThread instead of OutputJsonCtx,
but as the datatypes were similar enough no harm was done.
Now that they are using their proper datatype, removed
AlertJsonThread from output.h as its no longer used.
Set flags by default:
-Wmissing-prototypes
-Wmissing-declarations
-Wstrict-prototypes
-Wwrite-strings
-Wcast-align
-Wbad-function-cast
-Wformat-security
-Wno-format-nonliteral
-Wmissing-format-attribute
-funsigned-char
Fix minor compiler warnings for these new flags on gcc and clang.